File: /usr/src/linux/drivers/atm/nicstarmac.c
1 /*
2 * this file included by nicstar.c
3 */
4
5 /*
6 * nicstarmac.c
7 * Read this ForeRunner's MAC address from eprom/eeprom
8 */
9
10 #define CYCLE_DELAY 5
11
12 /* This was the original definition
13 #define osp_MicroDelay(microsec) \
14 do { int _i = 4*microsec; while (--_i > 0) { __SLOW_DOWN_IO; }} while (0)
15 */
16 #define osp_MicroDelay(microsec) {unsigned long useconds = (microsec); \
17 udelay((useconds));}
18
19
20 /* The following tables represent the timing diagrams found in
21 * the Data Sheet for the Xicor X25020 EEProm. The #defines below
22 * represent the bits in the NICStAR's General Purpose register
23 * that must be toggled for the corresponding actions on the EEProm
24 * to occur.
25 */
26
27 /* Write Data To EEProm from SI line on rising edge of CLK */
28 /* Read Data From EEProm on falling edge of CLK */
29
30 #define CS_HIGH 0x0002 /* Chip select high */
31 #define CS_LOW 0x0000 /* Chip select low (active low)*/
32 #define CLK_HIGH 0x0004 /* Clock high */
33 #define CLK_LOW 0x0000 /* Clock low */
34 #define SI_HIGH 0x0001 /* Serial input data high */
35 #define SI_LOW 0x0000 /* Serial input data low */
36
37 /* Read Status Register = 0000 0101b */
38 static u_int32_t rdsrtab[] =
39 {
40 CS_HIGH | CLK_HIGH,
41 CS_LOW | CLK_LOW,
42 CLK_HIGH, /* 0 */
43 CLK_LOW,
44 CLK_HIGH, /* 0 */
45 CLK_LOW,
46 CLK_HIGH, /* 0 */
47 CLK_LOW,
48 CLK_HIGH, /* 0 */
49 CLK_LOW,
50 CLK_HIGH, /* 0 */
51 CLK_LOW | SI_HIGH,
52 CLK_HIGH | SI_HIGH, /* 1 */
53 CLK_LOW | SI_LOW,
54 CLK_HIGH, /* 0 */
55 CLK_LOW | SI_HIGH,
56 CLK_HIGH | SI_HIGH /* 1 */
57 };
58
59
60 /* Read from EEPROM = 0000 0011b */
61 static u_int32_t readtab[] =
62 {
63 /*
64 CS_HIGH | CLK_HIGH,
65 */
66 CS_LOW | CLK_LOW,
67 CLK_HIGH, /* 0 */
68 CLK_LOW,
69 CLK_HIGH, /* 0 */
70 CLK_LOW,
71 CLK_HIGH, /* 0 */
72 CLK_LOW,
73 CLK_HIGH, /* 0 */
74 CLK_LOW,
75 CLK_HIGH, /* 0 */
76 CLK_LOW,
77 CLK_HIGH, /* 0 */
78 CLK_LOW | SI_HIGH,
79 CLK_HIGH | SI_HIGH, /* 1 */
80 CLK_LOW | SI_HIGH,
81 CLK_HIGH | SI_HIGH /* 1 */
82 };
83
84
85 /* Clock to read from/write to the eeprom */
86 static u_int32_t clocktab[] =
87 {
88 CLK_LOW,
89 CLK_HIGH,
90 CLK_LOW,
91 CLK_HIGH,
92 CLK_LOW,
93 CLK_HIGH,
94 CLK_LOW,
95 CLK_HIGH,
96 CLK_LOW,
97 CLK_HIGH,
98 CLK_LOW,
99 CLK_HIGH,
100 CLK_LOW,
101 CLK_HIGH,
102 CLK_LOW,
103 CLK_HIGH,
104 CLK_LOW
105 };
106
107
108 #define NICSTAR_REG_WRITE(bs, reg, val) \
109 while ( readl(bs + STAT) & 0x0200 ) ; \
110 writel((val),(base)+(reg))
111 #define NICSTAR_REG_READ(bs, reg) \
112 readl((base)+(reg))
113 #define NICSTAR_REG_GENERAL_PURPOSE GP
114
115 /*
116 * This routine will clock the Read_Status_reg function into the X2520
117 * eeprom, then pull the result from bit 16 of the NicSTaR's General Purpose
118 * register.
119 */
120
121 u_int32_t
122 nicstar_read_eprom_status( virt_addr_t base )
123 {
124 u_int32_t val;
125 u_int32_t rbyte;
126 int32_t i, j;
127
128 /* Send read instruction */
129 val = NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE ) & 0xFFFFFFF0;
130
131 for (i=0; i<sizeof rdsrtab/sizeof rdsrtab[0]; i++)
132 {
133 NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
134 (val | rdsrtab[i]) );
135 osp_MicroDelay( CYCLE_DELAY );
136 }
137
138 /* Done sending instruction - now pull data off of bit 16, MSB first */
139 /* Data clocked out of eeprom on falling edge of clock */
140
141 rbyte = 0;
142 for (i=7, j=0; i>=0; i--)
143 {
144 NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
145 (val | clocktab[j++]) );
146 rbyte |= (((NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE)
147 & 0x00010000) >> 16) << i);
148 NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
149 (val | clocktab[j++]) );
150 osp_MicroDelay( CYCLE_DELAY );
151 }
152 NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE, 2 );
153 osp_MicroDelay( CYCLE_DELAY );
154 return rbyte;
155 }
156
157
158 /*
159 * This routine will clock the Read_data function into the X2520
160 * eeprom, followed by the address to read from, through the NicSTaR's General
161 * Purpose register.
162 */
163
164 static u_int8_t
165 read_eprom_byte(u_int32_t base, u_int8_t offset)
166 {
167 u_int32_t val = 0;
168 int i,j=0;
169 u_int8_t tempread = 0;
170
171 val = NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE ) & 0xFFFFFFF0;
172
173 /* Send READ instruction */
174 for (i=0; i<sizeof readtab/sizeof readtab[0]; i++)
175 {
176 NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
177 (val | readtab[i]) );
178 osp_MicroDelay( CYCLE_DELAY );
179 }
180
181 /* Next, we need to send the byte address to read from */
182 for (i=7; i>=0; i--)
183 {
184 NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
185 (val | clocktab[j++] | ((offset >> i) & 1) ) );
186 osp_MicroDelay(CYCLE_DELAY);
187 NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
188 (val | clocktab[j++] | ((offset >> i) & 1) ) );
189 osp_MicroDelay( CYCLE_DELAY );
190 }
191
192 j = 0;
193
194 /* Now, we can read data from the eeprom by clocking it in */
195 for (i=7; i>=0; i--)
196 {
197 NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
198 (val | clocktab[j++]) );
199 osp_MicroDelay( CYCLE_DELAY );
200 tempread |= (((NICSTAR_REG_READ( base, NICSTAR_REG_GENERAL_PURPOSE )
201 & 0x00010000) >> 16) << i);
202 NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE,
203 (val | clocktab[j++]) );
204 osp_MicroDelay( CYCLE_DELAY );
205 }
206
207 NICSTAR_REG_WRITE( base, NICSTAR_REG_GENERAL_PURPOSE, 2 );
208 osp_MicroDelay( CYCLE_DELAY );
209 return tempread;
210 }
211
212
213 void
214 nicstar_init_eprom( virt_addr_t base )
215 {
216 u_int32_t val;
217
218 /*
219 * turn chip select off
220 */
221 val = NICSTAR_REG_READ(base, NICSTAR_REG_GENERAL_PURPOSE) & 0xFFFFFFF0;
222
223 NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
224 (val | CS_HIGH | CLK_HIGH));
225 osp_MicroDelay( CYCLE_DELAY );
226
227 NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
228 (val | CS_HIGH | CLK_LOW));
229 osp_MicroDelay( CYCLE_DELAY );
230
231 NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
232 (val | CS_HIGH | CLK_HIGH));
233 osp_MicroDelay( CYCLE_DELAY );
234
235 NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
236 (val | CS_HIGH | CLK_LOW));
237 osp_MicroDelay( CYCLE_DELAY );
238 }
239
240
241 /*
242 * This routine will be the interface to the ReadPromByte function
243 * above.
244 */
245
246 void
247 nicstar_read_eprom(
248 virt_addr_t base,
249 u_int8_t prom_offset,
250 u_int8_t *buffer,
251 u_int32_t nbytes )
252 {
253 u_int i;
254
255 for (i=0; i<nbytes; i++)
256 {
257 buffer[i] = read_eprom_byte( base, prom_offset );
258 ++prom_offset;
259 osp_MicroDelay( CYCLE_DELAY );
260 }
261 }
262
263
264 /*
265 void osp_MicroDelay(int x) {
266
267 }
268 */
269
270